// @(#)Meter.java   9/2002
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package drcl.diffserv;

import drcl.net.*;

/**
This defines the base class for a meter.
Subclasses needs to override: {@link #measure(drcl.net.Packet, double)},
{@link #reset()}, {@link #duplicate(Object)} and {@link #info(String)}.

@author Rong Zheng (zhengr@ee.eng.ohio-state.edu)
version 1.0 07/16/00   
  */ 
public abstract class Meter extends drcl.DrclObj
{
  public Meter()
  { super(); }
  
  /** Returns the label for the packet based on the measurement and
  the agreement of the connection the packet belongs to.  */
  protected abstract int measure(Packet p, double now_);
  
  /** Resets this meter to be used anew. */
  public abstract void reset();

  public abstract void duplicate(Object source_);
  
  public String info()
  { return info(""); }

  /** Prints out the content of this meter.
  @param prefix_ prefix that should be prepended to each line of the result.*/
  public abstract String info(String prefix_);
}
